which bit cant you do? If you find a photo on the internet then right click it, go to properties and copy (ctrl+c) its address then in here type in [*img=ADDRESS] (without the *). If the photo is on your computer then upload it to say imageshack www.imageshack.us (the instructions are very simple on there) and copy the address that it gives you under the 'direct link to image' bit (or something similar to that anyway) then in here type in [*img=ADDRESS] (without the *). Couldnt be simpler
For instance You need to type this to get the photo of your dog in your avatar into the post (remove the *). [*img=http://img229.imageshack.us/img229/986/picture028rw7.jpg] I got the bit in bold by right clicking on your avatar, click on properties (at the bottom of the menu), highlight the address URL, hold down CTRL and C to copy, then come to your post and press CTRL and V to paste what you have just copied in the post.